一种基于远场图像的稀疏光学合成孔径系统共相探测新方法的仿真研究

稀疏光学合成孔径系统中,共相探测环节检测子孔径间的相位平移误差,为系统高分辨力的实现提供重要支持. 文章从基本的物理原理出发,分析了系统远场与相位平移误差的关系,并以此为基础,从数学上阐明了 相位平移误差对系统远场图像的影响机制.进一步,针对典型的两孔径系统,提出了一种新的基于远场相似度 的共相探测方法,并对其可行性、原理性偏差和动态范围进行了仿真分析.结果表明,该方法在原理上可实现 对两孔径系统相位平移误差的良好标定,且避免了一些既有方法可能存在的2π模糊性及无法判断符号的问题,具有一定的动态范围,为共相探测新技术的进一步研究提供了有效参考.

Analysis of an Co-phasing detecting method based on far-field images of sparse-optical-synthetic-aperture system

For the sparse-optical-synthetic-aperture telescope system,the co-phasing detection plays an important role for the realization of system’s high resolution in solving out piston errors between sub-apertures.In this paper,the relationship between piston error and system’s far-field intensity was analyzed based on physical principles,then the impact of piston error on system’s far-field images was clarified theoretically.Furthermore,an innovative co-phasing detecting method based on the far-field images’ similarity was approved for the bi-sub-aperture systems,with its feasibility,detecting deviation and dynamic range were researched by simulation.The results proved that,with this method,the piston error between the system’s two sub-apertures can be soundly detected principally while immune from the problems of 2πambiguity and direction decision that might exist within some other co-phasing detecting methods. Plus its dynamic range shown from these results,this new co-phasing detecting method provides effective references for deeper research of co-phasing detecting techniques.